Thursday, 8 December 2011

Development of Empathy in Infants

Babies are notoriously selfish creatures - either they're asleep, happy, or they're screaming. It isn't until the age of two that children begin to realise that other people have their owns wants and needs.

However, a recent study from researchers at Durham University has demonstrated that infants as young as six-months old already show emotional responses to the expressions of others, with a bias towards stronger reactions to negative emotions. This work has implications for our understanding of the development of empathy.

Empathy is the capacity to recognise another’s feelings, effectively allowing us to put ourselves in someone else’s mental shoes. This ability is essential for successful interactions with others, as demonstrated by a number of disorders in which a person is unable to sense or reciprocate the emotions of others. For example, it is thought that some of the neural processes required for empathy are dysfunctional in psychopaths and there is a large body of on-going work relating to the relationship between empathy, or lack of, and autism spectrum disorders.

The development of empathy, however, is a poorly understood area. While it has been observed that infants can discriminate between different emotional expressions and respond with matching emotions, it is unknown whether this is a simple emotional response or if mimicry of a particularly expression is involved. The latter would represent an unconscious mechanism involved in the development of empathy.

An interesting observation is that, in both children and adults, there is a bias towards responses to negative emotions. This manifests in, for example, a larger increase in brain activity in response to an angry voice than to a happy voice. In simplistic terms, this is explainable by the association between negative emotions and a potential threat—an early warning sign that the cause of another’s unhappiness may spread to others in the vicinity. In comparison, less is known about the sensing of positive emotions by infants.

In the study published in PLoS One, researchers used pupil dilation as a measure of an infant’s response to a video recording of various emotional expressions. Pupil size is commonly used as a measure of arousal—this can be in the positive sense, such as when an infant is shown a photograph of its mother, or negative, such as in the case of children and adults which both show an increase in pupil diameter upon witnessing harm occurring to another person.

The researchers found that infants respond to both positive and negative emotions at 6 and 12-months of age. However, a previous hypothesis that the bias towards negativity occurs at the end of the first year was only partially supported. From the data, it appeared that this bias was already present in the 6-month-olds. Studies such as this pave the way towards a better understanding of the development of empathy in humans and have implications for the understanding of early childhood happiness.